JPH02101933A - Method and apparatus for protecting engine-starting auxiliary battery - Google Patents

Abstract

PURPOSE:To protect batteries securely by cutting OFF the connection of an engine-starting car-loaded battery and auxiliary batteries connected in parallel with said car-loaded battery, when the voltage of at least one of auxiliary batteries falls or rises from a specified value. CONSTITUTION:An engine-starting car-loaded battery 2 is connected in parallel with auxiliary batteries 4, 5 by booster cables 10, 11. The series-parallel connection of said auxiliary batteries 4, 5 is changed by a manual switch 6 according to the voltage of said car-loaded battery 2. When it is detected 18 that the voltage of said auxiliary battery 5 lowers from a specified value and when the voltage drop between both ends 7, 11 of said booster cable 10 is more than a given value, comparison circuits 17 and 18 output power to turn ON AND 20. When the voltage of the auxiliary battery 5 is more than said specified value, said comparison circuit 19 is turned ON. In either case, said circuits are triggered 22 via OR circuit 21, a thyristor 23 is turned ON, a breaker 9 is tripped 24, and a buzzer 25 is rung. Thus, the false connection of said auxiliary batteries is prevented so that batteries are protected securely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and device for protecting against connection errors of an auxiliary engine starting battery.

[Conventional technology]

In particular, serials used at construction sites are often extremely expensive to purchase or lease, but not only that, but the introduction of serials into the work process requires sufficient scheduling. This is done at the most appropriate time and in the shortest possible time, so if the body stops unexpectedly, the impact would be extremely large. The most common and common failure is when a vehicle's battery is fully discharged, making it impossible to start the engine and causing the vehicle or onboard equipment to stop working until the battery can be replaced or recharged. be. In such cases, there is an urgent need to shorten downtime as much as possible. Therefore, as a countermeasure, always have a spare auxiliary battery on hand, and if the engine cannot be started to operate the vehicle or mounted equipment due to discharge of the vehicle battery, connect the auxiliary battery in parallel and immediately start the engine. It has become commonplace to be able to start the car. Similar requirements can be found in various types of business.For example, in the agricultural field, concentrated work is required at appropriate times, and unexpected stoppages are a serious factor hindering efficiency, so the above-mentioned auxiliary battery Nito. But it has become a necessity.

By the way, the people who carry out such work are not necessarily experts in the work concerned, and it cannot be expected that they will be proficient in handling the auxiliary battery, which is only needed when an abnormality occurs. Furthermore, when working at night, even experienced workers may make mistakes. In this way, it is often seen in practice that the wrong pole of the vehicle battery is connected to the auxiliary battery, causing a large spark. In serial programs that use large-capacity batteries, sparks can cause molten metal to fly more than 1 meter away. Not only is there a risk of burns to workers from these sparks, but
If this is a construction site, fuel oil, paint, wood, etc.
This is a serious safety issue as there is a possibility of igniting combustible materials that are abundant in the surrounding area and causing a fire.

Needless to say, even if a major accident does not occur, the auxiliary battery may be damaged or consumed unnecessarily. As a measure to prevent accidents caused by such reverse connections, a method is used to detect overcurrent at the time of connection and cut off the connecting line, but since the current that must be passed when starting the engine is also large, it is necessary to lower the detection current rating. However, it is difficult to avoid this, and it is inevitable that the operating time will be longer in the event of an abnormality, and that the battery will be damaged in some way. Therefore, it has been desired to develop a method that enables faster operation. Additionally, as disclosed in Japanese Utility Model Application Publication No. 59-71568, a diode is inserted in the opposite direction between the lines on the side of the booster cable near the vehicle battery, and if the connection is reversed, current will flow. A method has been proposed to detect and judge the battery, but when actually connecting the batteries in reverse, a closed circuit is formed that connects both batteries in series.
Since the potential at the location where the diode is connected depends on the resistance balance of the booster cable and the current, the current flowing through the diode is uncertain, and the reliability of this method is far from practical. The above method also has the drawback that the detection circuit operates in reverse if the connection of the booster cable to the auxiliary battery side is reversed.

Furthermore, even if the voltage specifications of the vehicle battery change, when using a corresponding type of auxiliary battery device by switching between series and parallel connections of battery units with a switch,
In addition to the above-mentioned reverse connection mistakes, it is often the case that the vehicle battery and the auxiliary battery are connected with the wrong voltage rating, in which case, for example, the charging reaction that takes place in the auxiliary battery generates hydrogen gas, which in extreme cases The battery may be damaged.

It goes without saying that if an incorrect connection is detected, it is preferable that the operation cannot be performed again unless the connection is changed.

[Problem to be solved by the invention]

In view of the above, it is an object of the present invention to provide an engine starting auxiliary battery protection method and protection device that automatically disconnects and warns when there is a reverse connection or voltage mismatch when connecting an auxiliary battery to an on-vehicle battery.

[Means to solve the problem]

In order to achieve the above object, the engine starting auxiliary battery protection method according to the present invention is provided such that the terminal voltage of the auxiliary battery is lower than a predetermined value, and the voltage drop between the auxiliary battery and the booster cable terminal is a predetermined value. It is characterized by cutting off the connection with the vehicle battery when it detects that the battery is larger than that.

In addition to the above, another engine starting auxiliary battery protection method according to the present application is characterized in that, in addition to the above, the connection with the in-vehicle battery is cut off when the terminal voltage of the auxiliary battery connected to the in-vehicle battery is higher than a predetermined value. shall be.

The engine starting auxiliary battery protection device according to the present application, which directly implements the above protection method, uses an engine starting auxiliary battery unit consisting of one or more batteries, and the terminal voltage of the auxiliary battery is lower than a predetermined voltage. a comparison circuit that detects that the voltage drop between the potential of the terminal of the auxiliary battery unit coupled to the on-board battery and the connection terminal for the booster cable that connects to the on-board battery is higher than a predetermined voltage; It is characterized by comprising a comparison circuit and a circuit breaker that cuts off the connection between the auxiliary battery and the vehicle battery when both comparison circuits output detection signals. Another engine starting auxiliary battery protection device according to the present application includes, in addition to the above-mentioned protection device, a comparison circuit that detects that the terminal voltage of the auxiliary battery is higher than a predetermined voltage, and the detection signal also causes the shutoff. It is characterized by being designed to operate a device.

Still another engine starting auxiliary battery protection device according to the present application includes an alarm buzzer that sounds at the same time as the circuit breaker is activated, and a ground terminal of the alarm buzzer is connected to the on-vehicle battery side of the track to be cut off. It is characterized by

[For production]

If the auxiliary battery unit and the vehicle battery are connected with the booster cable with their electrodes in the wrong direction, both batteries will be connected in series during a closed circuit, and the terminal voltage of any auxiliary battery in the circuit will be extremely high. At the same time, a large current flows from the auxiliary battery to the vehicle battery. According to the present application, since these can be detected with high sensitivity and high speed only inside the device, it is possible to quickly disconnect erroneous conductor connections without using any special external device.

In addition, if the terminal voltage of the auxiliary battery increases due to incorrect voltage rating even if the electrode polarity is correct, it is possible to immediately detect this and disconnect the conductor to prevent the auxiliary battery from being pressurized and charged. can.

Furthermore, if the ground terminal of the alarm buzzer is connected to the vehicle battery side of the circuit breaker, the alarm buzzer will sound at the same time as the circuit breaker is activated, but even after the circuit breaker is activated and the connecting conductor is severed. Because it is connected to the negative electrode of the vehicle battery, it continues to play, and only stops when the operator disconnects the booster cable from the vehicle battery. In this way, since the buzzer continues to sound until the booster cable is reconnected, there is no need to turn on the switch again even if a careless operator performs the operation.

〔Example〕

The present invention will be described in detail below with reference to the illustrated embodiments.

The drawing is a block diagram showing one embodiment of the present invention. The engine starting auxiliary battery device (1) of this embodiment is equipped with two 12V storage batteries (4) and (5) that can be switched in series and parallel by manually operating a switch (6). In other words, when the on-board engine battery (2) to be started is 12V, the switch (6) is switched to connect both batteries in parallel, and when the voltage is 24V, the batteries are connected in series, so that both batteries can be used. It is. The positive terminal (7) of the auxiliary battery device (1)
) and the negative terminal (8) with a pair of booster cables (10
) and (11) respectively, the in-vehicle battery (2
) is used by connecting it to the positive and negative terminals of the The onboard battery is connected to the engine starting circuit (3).
The negative terminal (8) of the auxiliary battery is attached to the negative conductor of the auxiliary battery.
There is a no-fuse breaker (9) in between, which can be shut off manually or automatically.

A sufficiently thick conductive wire is used for the positive electrode side conductor to connect the positive electrode of the auxiliary battery and the positive electrode side terminal (7) on the operation surface of the device. It goes without saying that each storage battery can be replaced, and that it can also be charged using a charging device not shown. Additionally, lighting equipment will be installed for night work.

This embodiment is an engine starting auxiliary battery device which has the functions of the conventional device described above and further includes a protection circuit against incorrect connection. Detection circuit part of protection circuit (15
) detects the following three conditions, processes them to determine an abnormality, and operates the alarm buzzer and no-fuse breaker drive circuit (16).

First of all, if you connect the booster cable (10) incorrectly,
, (11), and in reality, it is detected at the point (12) near the positive terminal of (4), (5) (one terminal point of the auxiliary battery connected to the vehicle battery (2)). This is done by detecting whether or not the potential difference between the positive terminal (7) on the operation surface of the device and the positive terminal (7) is greater than a predetermined value. This connects the power supply voltage to the resistor (30), (31
This can also be carried out using an ordinary operational amplifier (17) whose inverting input terminal receives a comparison voltage obtained by appropriately dividing the voltage at (). That is, the voltage at the battery one terminal point (12) is inputted to the non-inverting input terminal of the operational amplifier (17) via the input resistor, and the voltage at the operating surface terminal point (7) is inputted by human input having the same resistance value. If it is input to the inverting input terminal via a resistor, the operational amplifier (17) compares the difference between the two types of pressure with the comparison voltage, and if the former is larger, outputs an output signal saturated in the positive direction. put out.

The resistance of the conductive wire between the picture points is extremely small in accordance with the purpose of the device to supply as large a current as possible, but for example, if the resistance of the conductive wire is 1 mΩ, a voltage of 0.3 V will be generated when a current of 300 A flows. Since the drop occurs, sufficient sensitivity can be ensured. Note that the comparison voltage can be obtained by using a separate reference battery or more simply by using a forward voltage drop of a diode, depending on the value to be set. In addition, it goes without saying that the arithmetic processing performed using one operational amplifier in the above example may be performed using two comparators, or may be performed by AD converting the voltage and using digital arithmetic processing means. be.

The second condition to be detected is an abnormal drop in the voltage at one terminal of the auxiliary battery. If the connection is reversed, a current flows and at the same time the terminal voltage of the storage battery is greatly reduced. Therefore, by detecting the excessive current together with the above-mentioned excessive current, incorrect connection can be reliably determined.

In addition, the voltage drop at this time occurs in the same way in all storage batteries connected in series, so it is not necessarily necessary to directly measure the voltage supplied to the vehicle battery, but rather to the battery used as the power source for the protection circuit. It is sufficient to detect the terminal voltage of A comparator (18) compares the terminal voltage (13) of the storage battery (5) with a predetermined threshold and outputs an output if it is low. As a comparator, the input terminals to be compared are introduced into a circuit consisting of a reverse Zener diode and two resistors connected in series, and the voltage at the midpoint of both resistors is passed through another resistor whose emitter is grounded. If the configuration is such that it leads to the base of the switching transistor, it is easy to create an arbitrary threshold value with a simple design. That is, if the terminal voltage (13) is high enough to exceed the Zener voltage, the transistor will conduct because current flows through the resistor and the voltage at the midpoint of both resistors forward biases the base with respect to the emitter. On the other hand, when the terminal voltage decreases, the current flowing through the Zener diode becomes smaller or is cut off, and the voltage at the intermediate point drops, so the transistor is cut off and the collector voltage increases. The voltage at which this switching occurs can be varied by the Zener voltage and the resistance value of the resistor.

The detection output of the operational amplifier (17) and the comparator (18)
) is input to an AND circuit (20), where it is determined whether there is a reverse connection.

The third condition to be detected is an abnormal rise in the terminal voltage of the auxiliary battery. Auxiliary batteries are connected in parallel 1
If you make a mistake such as connecting to a 24V car battery when the output is 2V, the auxiliary battery will receive high voltage charging from the car battery and the terminal voltage will abnormally rise to about 18V, for example. Since the voltage increase at this time also occurs in the storage battery (5-inch) used as the power source for the protection circuit, the above-mentioned erroneous operation can be detected only from the terminal voltage of the storage battery.

A comparator (19) compares the terminal voltage (13) of the storage battery (5) with a predetermined threshold, for example 15V, and outputs a detection signal if it is higher than that. At this time, similarly to the above, a circuit is provided in which a Zener diode in the opposite direction and two resistors are connected in series, and the circuit is led from the midpoint between the two resistors through the resistor to the base of the switching transistor. The comparator for the above purpose can be constructed by: That is, if the terminal voltage (13) is a normal value, the voltage at the midpoint biases the base in the opposite direction to the emitter, so the transistor is cut off and the collector voltage is high, but the terminal voltage When the voltage becomes high enough to exceed the Zener voltage, the transistor becomes conductive and the collector voltage decreases. When the comparator configured in this manner detects a rating mismatch with the on-board battery, the output is reduced to notify the user of the mismatch. It can function in the same way even if the vehicle battery is rated at 36V or 48V.

said comparator (1) indicating a battery voltage rating mismatch;
The detection output of 9) and the detection output of the AND circuit (20) that instructs reverse connection of the booster cable are connected to the OR circuit (20).
1) is entered. When any of the above is detected, the trigger circuit (22) receives the output of the OR circuit (21) and generates a trigger to ignite the cyrisk (23) and energize the electromagnetic coil (24). to operate the no-fuse breaker (9). At this time, the alarm buzzer (2
5) Turn on the power and sound the buzzer. If the comparator is formed by the transistor circuit described above, it is necessary to use a sign converter depending on the sign of the detection output, but the essence of the logic remains the same. Such a no-fuse breaker has an operating time of several 10 milliseconds. This has a great effect compared to the overcurrent detection type that is commonly used in the past, which takes about 2 seconds to operate. Of course, since using both together is a combination of devices with different operating principles, it goes without saying that the overall reliability is further improved.

In this embodiment, the positive power supply line (28) of the protection circuit is connected to the positive internal terminal (1) of one auxiliary battery (5).
3) is connected through a diode (26) to a large-capacity electrolytic capacitor (27) where power is stored. In this way, the circuit power is taken from one battery (5), so batch! Since the power supply voltage does not change even if J-(4) and (5) are switched in series and parallel, circuit design is easy. Due to the presence of the diode (26), even if the auxiliary battery (5) is connected in the wrong direction, a reverse voltage will not be applied, so that the circuit elements will not be damaged. Also, the auxiliary battery (5) was connected incorrectly to the vehicle battery (2).
Even when the terminal voltage of the diode (26
) prevents discharge, and the operation of the no-fuse breaker (9) etc. can be ensured by storing electricity in the capacitor (27). The low voltage side power supply lines (14) and (29) of the protection circuit are as follows:
A portion (14) corresponding to the detection circuit (15) is connected to the negative electrode of the above-mentioned auxiliary battery (5) so that it is always activated. On the other hand, the part (2) of the drive circuit (16) of the alarm buzzer (25) and no-fuse breaker (9)
9) is connected to the in-vehicle battery (2) side from the no-fuse breaker (9), so even when the no-fuse breaker (9) operates and is disconnected from the auxiliary battery (5), the in-vehicle batch leak 2) The alarm buzzer (25) continues to sound due to the output of the booster, and only stops when the booster cable is removed.

According to the above configuration, in order to stop the alarm buzzer that starts sounding when the cable is incorrectly connected, the booster cable must be replaced correctly, so that no operator will make any further erroneous operations.

〔Effect of the invention〕

As described above, according to the method and apparatus of the present invention, even when operated by an inexperienced worker, an incorrect connection is detected and the line is automatically and instantaneously cut off. This prevents damage to the terminals and the battery itself, as well as danger from sparks, and also prevents damage to the battery and damage to the vehicle's electrical circuit elements that would occur if the voltage rating of the auxiliary battery was incorrectly connected.

Since the method of the present invention is a method of processing voltage signals with a logic circuit and cutting them off, compared to using a type of no-fuse breaker that detects and trips an excessive current flowing through a booster cable, which is commonly used in the past, The operating time is much faster and the battery can be reliably protected. In addition, since the detection target for detecting abnormalities is limited to the inside of the device,
It is possible to properly protect the engine starting battery device by adding a circuit only within the device without using a special booster cable.

Furthermore, the buzzer that sounds when a connection is incorrect will not stop ringing unless the connection is corrected, so there is no need to restart the device with an incorrect connection.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawing is a block diagram showing one embodiment of the present invention. (2)...In-vehicle badge') - (4), (5)・
...Auxiliary battery, (9) ...No fuse breaker, (15) ...Detection circuit, (1
6)...Drive circuit.

Claims (1)

[Claims] 1. When it is detected that the terminal voltage of at least one auxiliary battery (5) has decreased below a predetermined value, the connection with the on-vehicle battery (2) is cut off. Engine starting auxiliary battery protection method. 2. The voltage drop between the terminal (12) of the auxiliary battery unit and the booster cable connection terminal (7) is at least a predetermined value, and at least one auxiliary battery (
5) A method for protecting an engine starting auxiliary battery, characterized in that the connection with the on-vehicle battery (2) is cut off when it is detected that the terminal voltage of (5) has decreased below a predetermined value. 3. The engine starting auxiliary battery protection method according to claim 1 or 2, further comprising detecting that the terminal voltage of the at least one auxiliary battery (5) is higher than a predetermined value. Also, an engine starting auxiliary battery protection method characterized by cutting off the connection with the vehicle battery (2). 4. One or more batteries (4), (5)
A protection device for an engine starting auxiliary battery device (1) comprising: at least one auxiliary battery (5);
for a comparison circuit (18) that detects that the terminal voltage (13) of the is lower than a predetermined voltage, and a booster cable (10) that connects to the terminal (12) of the auxiliary battery unit that is coupled to the on-board battery and the on-board battery. A comparator circuit (17) that detects that the voltage drop between the connection terminals (7) of the A circuit breaker (
9) An engine starting auxiliary battery protection device comprising: 5. The engine starting auxiliary battery protection device according to claim 4, further comprising a comparison circuit (19) for detecting that the terminal voltage (13) of the one auxiliary battery (5) is higher than a predetermined voltage. , An engine starting auxiliary battery protection device characterized in that the circuit breaker (9) is operated also by the detection signal. 6. The engine starting auxiliary battery protection device according to claim 4 or 5, comprising an alarm buzzer (25) that sounds at the same time as the circuit breaker (9) operates, and a ground terminal (29) of the alarm buzzer. An engine starting auxiliary battery protection device characterized in that the device is connected to the on-vehicle battery side (8) of the track where the power is cut off.